Can you mix 10w30 oil with 10w40 in a 1991 Chrysler LeBaron?
Mixing different types of oil is generally not recommended. While 10w30 and 10w40 are both motor oils with similar viscosities, they have different additives and properties that may not mix well. Mixing the two oils could potentially lead to engine damage or reduced performance. It's best to refer to your vehicle's owner's manual for the recommended oil type and viscosity.